This invention relates to a method for monitoring the track generated by the control of the drives of a computer controlled machine tool or an industrial robot, in general, and more particularly, to a method for comparing reference values stored in a user program with the corresponding actual values of the track travel distance for undue deviations.
Computer controlled machine tools are well known (see, for instance, DE-AS No. 27 29 372), in which, for monitoring the drives and therefore, also the contour traveled, the drag distance, i.e., the deviation between a distance reference value and the actual distance value is checked and a trouble signal is given in the event of unpermissible deviations. In such controls, it is also known to form the ratio of the cyclically determined partial-distance, actual values and the corresponding speed reference values, and also to use a deviation from a given ratio as an indication of trouble.
It is an object of the present invention to provlde a simple monitoring system, with which it is possible to check whether the desired track stored in the user program can be maintained with predetermined velocities and operating conditions.